1. Field of the Invention
This invention relates to a hybrid-driven device with a battery and a fuel cell as power sources of a drive motor for mobile devices such as vehicles, watercrafts, and the like.
2. Background Art
A hybrid type electric car has been developed for the purpose of reducing pollution generated by vehicles, which includes an electric motor for driving the vehicle. Two kinds of batteries, for constant speed running and high output running, are combined as power sources of the vehicle to increase travel distance for each charge and to provide efficient and stable power supply during constant speed running and high output running, such as acceleration. In such a hybrid-driven vehicle, a system has been contemplated in which methanol is used as primary fuel, and a fuel cell is used as a power supply source. This system includes a reformer and a shift reactor for processing carbon monoxide, and a secondary battery in addition to the power supply source, such as a lead battery, for carrying peak load. In such a hybrid-driven vehicle, a vehicle controller is provided for controlling the motor in an optimum condition by supplying electric power efficiently in response to the operating conditions after actuation of the power source. Modules constituting equipment such as a motor, a fuel cell and a battery are provided with sensors for detecting data, such as temperature, rpm or a state of the voltage and current, corresponding to the modules necessary for drive control of the vehicle, respectively. The vehicle controller calculates required electric power or expected travel distance according to the detected output, for charging/discharging of the battery and the fuel cell, and drive control of the motor, or the like.
In constructing such a control system, it is desirable for each module to be easily installed into the vehicle and so as to provide easy parts replacement including that of related control system parts, for improved application of modules, and also to receive reliable control data, for more reliable control.
In driving a vehicle using two power sources such as a battery and a fuel cell described above, the vehicle controller calculates expected travel distance from the data on the residual amount of power source capacities and fuel in the normal operating conditions of both power sources, makes an effective use of the power sources during running while verifying reliable travel to the destination. The controller also makes proper use of the power sources, such as supplementary use of the battery to compensate for the delayed output response of the fuel cell during acceleration, so as to perform drive control of power sources through their controllers, for constant stable running.
However, if an abnormality occurs in the battery or the fuel cell, continuous use of the power sources might disable drive control based on the data from the power source controller, preventing stable running, and the abnormal state might expand more widely due to delayed measures against the abnormality, causing damage to other sections.
In view of the foregoing, it is a first object of this invention to provide a hybrid-driven vehicle capable of effecting improved efficiency of assembly and maintainability of modules forming a power system such as a motor and power supply sources such as a fuel cell and a battery, as well as reliable control.
In addition, it is a second object of this invention to provide a hybrid-driven vehicle in which the states of two power sources are detected during operation to calculate an approximate vehicle range based on the detection data, and the states of power sources are monitored constantly during operation such that the vehicle is able to travel smoothly to the destination.
Further, it is a third object of this invention to provide a hybrid-driven vehicle in which in the event that an abnormality is detected in either of the two hybrid drive power sources, the use of the power source is stopped promptly to prevent expansion of the abnormal state so as to cope with the abnormality immediately. Operation is continued using the other power source, for smooth drive control of the power system.
In order to achieve the foregoing first object, a first aspect of the invention includes a hybrid-powered vehicle having a first and a second power supply source, a main switch for switching on the power sources, and a device controller for controlling the device, wherein said power system and said first and second power supply sources are formed as integrated module units, respectively, each module unit is provided with a module controller a sensor for detecting the state of the module, and a sensor configured to store data indicative of the detected state.
In this arrangement, equipment constituting the power system such as a motor, the first power supply source such as a fuel cell and the second power supply source such as a battery, are arranged as module units such as a motor unit, a fuel cell unit and a battery unit, respectively, to be combined integrally together with related equipment and components, and incorporated unit by unit in a device such as a vehicle. The module units contain module controllers for controlling the respective modules. The module controllers have memory for storing detection data from state detection means of the modules, so that each module unit is able to perform data communication with the device controller.
By arranging the motor, fuel cell and battery as module units containing controllers, respectively, efficiency of assembly work and maintainability of modules are improved. Additionally control systems corresponding to the modules are integrated for the respective modules, thereby providing improved reliability of the control, easy parts replacement including that of the control system parts and improved applicability of modules with effective parts control.
In a preferred arrangement, the device controller is adapted to perform bidirectional data communication with the module controllers.
In this arrangement, data is stored in each module controller. The device controller can receive requisite data on request to the module controller. Thus, the memory structure is simplified on the device controller side and effective control can be performed on the same communication line for each module.
In another preferred arrangement, after a predetermined time has elapsed from a time when the main switch is turned off, preparation processing is performed on said first or said second power supply source for the next operation.
In this arrangement, after a predetermined time has elapsed from a time when the main switch is turned off, it is determined whether the capacity of the power supply source is optimized sufficiently for normal operation. Optionally when operation is stopped and the main switch is turned off, residual capacity of the first or the second power supply source is detected. Then, capacity-up processing is performed at a time earlier than the time of the next driving schedule entered by the user by a length of time necessary to increase the detected residual electric capacity up to an optimum value. Thus, the device can be held on standby in an optimum condition such that operation can be started stably and reliably at the time of next running for continued normal operation.
In addition, in order to achieve the second object, another aspect of this invention may provide a hybrid-powered vehicle with a first and a second power supply source as power sources for driving the vehicle, wherein an available amount of power supply by each of said first and said second power supply source is detected, and a controller is configured to calculate an approximate vehicle range from the available amount of power supply.
In this arrangement, during operation, the available amount of power supply of each of the first and the second power source, for example, residual capacity or residual fuel, is detected and the approximate vehicle range is calculated on the basis of the detected data. Thus, stable operation to the destination is verified and a prompt action can be taken when the approximate vehicle range or the residual quantity is insufficient.
In a preferred arrangement, this aspect of the invention is characterized in that said first power source is a fuel cell and said second one a battery. The fuel consumption ratio of the fuel cell and the capacity consumption ratio of the battery are calculated, and the approximate vehicle range is calculated on the basis of these consumption ratios. If said residual fuel of the fuel cell and said residual capacity of the battery are not more than the respective predetermined setting values, warning is indicated.
In this arrangement, the hybrid power source preferably comprises a fuel cell and a battery (secondary battery). The fuel consumption ratio of the fuel cell is calculated from the traveled distance and the fuel consumption, and the approximate vehicle range by the fuel cell is calculated from the fuel consumption ratio and the residual amount of fuel. Further, the capacity consumption ratio of the battery is calculated from the traveled distance and the voltage drop of the battery or the capacity consumption of the whole vehicle, and the approximate vehicle range is calculated from the capacity consumption ratio and the residual capacity. In this case, if the residual fuel and the residual capacity of the battery are not more than the respective predetermined values, warning is indicated and appropriate measures can be taken such as refueling and battery change, or charging.
In still another preferred arrangement, this aspect of the invention is characterized in that the characteristic data of capacity corresponding to the current and voltage of the battery is provided beforehand. The battery capacity is calculated from the detection data on the current or voltage of the battery, based on the characteristic data of capacity.
In this arrangement, the characteristic data of capacity corresponding to the current and voltage of the battery is stored beforehand in a ROM, etc. When the current or voltage of the battery is detected, the battery capacity (residual capacity) at the time of detection is calculated from the stored characteristic data of capacity, based on the detection data.
In another preferred arrangement, this aspect of the invention is characterized in that after a predetermined time has elapsed after a first detection data is obtained on said current or voltage, a second detection data is obtained on the current or voltage. The impedance is calculated from the calculated capacity value based on the first and the second detection data.
In this arrangement, after a predetermined time has elapsed after the battery capacity and the impedance are calculated on the basis of the first detection data, the capacity and the impedance are calculated on the basis of the second detection data. The state of discharge of the battery is identified from the impedance change. Taking account of this impedance change, the approximate vehicle range can be calculated on basis of the residual capacity of the battery.
Further, in order to achieve the third object, a further aspect of the invention can include a hybrid-driven device having a first and a second power supply source as power sources of a power system for driving the device. The first and second power supply sources are connected to said power system through first and second switches, respectively. A device controller is configured to control the device according to the operating conditions. The first and second power supply sources also have controllers, respectively. The controllers are adapted to detect abnormalities of the power supply sources and to store the detection data on abnormality. The device controller is adapted to perform bidirectional communication with the controllers of the power supply sources to send/receive data or commands, and to cut off the power supply source from said power system through the switches when said device controller receives said detection data indicating an abnormality.
In this arrangement, the device controller which controls the whole device is adapted to perform data communication with controllers of the power supply sources. If an abnormality occurs in any of the power supply sources and the abnormality is detected by its controller, the detection data is sent to the device controller, and the device controller determines which supply source the abnormality happens in, and cuts off the abnormal power supply source from the power system through the switches such as a relay. Thus, the use of the abnormal power source is stopped promptly and operation is continued using the other power source while an appropriate action is taken against the abnormality, thereby minimizing damage.
The abnormality of the power supply source can be detected by detecting the temperature and current or voltage of each power supply source. These values are determined to be abnormal when these values exceed the respective proper ranges. If such an abnormal state is detected, the detection data on the abnormality is stored in the controller of the abnormal power source and sent from the controller to the device controller on request.
In a preferred arrangement, this aspect of the invention is characterized in that the controller of each power supply source sends to said device controller a request signal for stoppage of discharging of the power supply source upon detection of abnormality of the power supply source. When the controller receives the request signal, the device controller cuts off the power supply source from said power system through the switches.
In this arrangement, the controller of each power supply source sends a signal requesting stoppage of discharging to stop the use of the power source upon detection of abnormality of the power source. The device controller which received the request signal for stoppage of discharging determines which power source the signal was sent from, and cuts off the power source from the power system through the switches occurs. Thus, when an abnormality occurs in a power source, a command can be requested for stopping the use of the power source, from the abnormal power source side, through communication between the controllers of the power sources and the device controller, providing a prompter action to cope with the abnormality. The request signal for stoppage of discharging may be simply the detection data on abnormality. In this case, if an abnormality is detected, the detection signal is sent to the device controller, and the device controller cuts off the abnormal power source accordingly.